Weather Topic: What is Precipitation?

Precipitation can refer to many different forms of water that may fall from clouds. Precipitation occurs after a cloud has
become saturated to the point where its water particles are more dense than the air below the cloud.

In most cases, precipitation will reach the ground, but it is not uncommon for precipitation to evaporate before it reaches the earth's
surface. When precipitation evaporates before it contacts the ground it is called Virga. Graupel, hail, sleet, rain, drizzle,
and snow are forms of precipitation, but fog and mist are not considered precipitation because the water vapor which
constitutes them isn't dense enough to fall to the ground.

Weather Topic: What is Sleet?

Sleet is a form of precipitation in which small ice pellets are the primary components. These ice pellets
are smaller and more translucent than hailstones, and harder than graupel. Sleet is caused by specific
atmospheric conditions and therefore typically doesn't last for extended periods of time.

The condition which leads to sleet formation requires a warmer body of air to be wedged in between two sub-freezing
bodies of air. When snow falls through a warmer layer of air it melts, and as it falls through the next
sub-freezing body of air it freezes again, forming ice pellets known as sleet. In some cases, water
droplets don't have time to freeze before reaching the surface and the result is freezing rain.